Trumpet / Cornet players all tend to hit very frustrating times during their playing / practice life. Some of those frustrations are short lived, while others can be what feels like forever.
The term "take it one day at a time" doesn't sound like it would help and a bit cliche', but it's true. Each day is a new practice session for every trumpeter! Some players let the feeling of being overwhelmed and frustrated get to the boiling point. So all they focus on IS the frustration and they stop looking for the solution.
If this sounds like you, I suggest taking a step back and allow yourself to forget about the frustrating problem... start looking for a simple answer. Most problems only get larger or stay in our paths because we try to find overly complicated solutions. Break down in your mind the movements that should be in the action and the movements that should not! Such as - articulation. Your tongue should be moving in a Dah - Gah pattern for double tonguing... if when you're playing, your tongue feels as though it's in a different position from when you're speaking it, make it feel the same. With range, the simple answer is keep the air speed up and the aperture small without pinching the lips together.
Hope this gives some insight to simple ways of over coming the frustration!
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